From: Paul Emmerich <emmericp@net.in.tum.de>
To: Ajinkya D Kadam <ajinkya.kadam@nyu.edu>, users@dpdk.org
Subject: Re: [dpdk-users] TimeStamping Packets Generated and Received via Pktgen Application
Date: Mon, 17 Oct 2016 00:55:51 +0200 [thread overview]
Message-ID: <30743c45-8247-ebf6-45ae-55d95e9bdfce@net.in.tum.de> (raw)
In-Reply-To: <CAOX3V8SUmvzXZthA14OBpTE0ro1wG+f1wb7dJVyzQyBaGEBq2Q@mail.gmail.com>
Hi,
Ajinkya D Kadam:
> If yes I would like to modify the pktgen code so that each transmitting and
> received packet is timestamped. Right now I am exploring the example
> applications like rxtx_callbacks which timestamps packets in DPDK, Is this
> the right direction to go ?
Check out my packet generator MoonGen
https://github.com/emmericp/MoonGen
It uses the hardware timestamping features (PTP) to do latency
measurements in the nanosecond-range.
However, if you will run into hardware limitations if you want to
timestamp *all* packets. This is sometimes supported on RX (e.g., i310,
X550) but I don't know a NIC that supports this on TX.
As for the precision that is achievable: ~10ns (depending on the NIC)
with hardware support. Software timestamping will typically result in a
standard deviation of 200-300ns under load and there will be huge outliers.
Paul
next prev parent reply other threads:[~2016-10-16 22:55 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-10-16 22:33 Ajinkya D Kadam
2016-10-16 22:55 ` Paul Emmerich [this message]
2016-10-17 8:01 ` Ajinkya D Kadam
2016-10-17 10:41 ` Paul Emmerich
2016-10-22 10:19 ` Huynhtu Dang
2016-10-25 11:07 ` Paul Emmerich
2016-10-27 7:27 ` Huynhtu Dang
[not found] ` <58A6F009-9B14-4CA2-87E5-54ABDB18D5F7@net.in.tum.de>
2016-12-06 15:40 ` Ajinkya D Kadam
2016-12-06 16:32 ` Paul Emmerich
[not found] ` <96BD8530-7724-4ABA-9D93-47C4FBD409DA@net.in.tum.de>
2016-12-14 18:33 ` Ajinkya D Kadam
2016-12-14 21:05 ` Paul Emmerich
2016-12-15 0:00 ` Ajinkya D Kadam
2016-12-19 17:51 ` Ajinkya D Kadam
2016-12-19 18:16 ` Paul Emmerich
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